Medical elongated body and medical instrument set

ABSTRACT

A rapid exchange type medical elongated body is disclosed in which an outer diameter of a distal portion of a tubular member is set smaller than an outer diameter of a proximal portion of the tubular member, which prevents an occurrence of a kink in a physical property change region of the medical elongated body which has a relatively large change in physical property. A tubular member forming a second region of a distal member of a medical elongated body is integrally formed with a shaft portion. The distal member has a reinforcement layer containing a metallic material and formed between an inner layer and an outer layer from a first region to the second region. The reinforcement layer is disposed inside the tubular member in the second region. An outer diameter of the first region is set smaller than an outer diameter of the second region.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/JP2018/012430 filed on Mar. 27, 2018, which claims priority toJapanese Application No. 2017-071981 filed on Mar. 31, 2017, the entirecontent of both of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a medical elongated body and a medicalinstrument set.

BACKGROUND ART

When performing various procedures on a body lumen such as blood vessel,an operator delivers a guiding catheter (parent catheter) to a locationclose to a lesion area, for example, to an entrance portion of acoronary artery along a guide wire which has been inserted into theblood vessel in advance. After having guided a distal portion of theguiding catheter to the location close to the lesion area, for example,to the entrance portion of the coronary artery, the operator enables atreatment device such as balloon catheter to advance from the distalportion of the guiding catheter, and performs a procedure on the lesionarea (for example, a stenosed site formed in the blood vessel).

For example, when the operator performs a procedure on the stenosed siteformed in the coronary artery, if the stenosed site is spaced apart fromthe entrance of the coronary artery, since the treatment device receivesvarious resistance due to influences of intravascular stenosis or thetortuousness of the blood vessel, it becomes relatively difficult forthe operator to insert the treatment device to the lesion area. In thiscase, after having disposed the guiding catheter at a predeterminedlocation inside the blood vessel, the operator inserts a medicalelongated body (child catheter) into the guiding catheter, and deliversthe medical elongated body to a position as close to the lesion area aspossible. The operator is capable of relatively easily inserting thetreatment device into the lesion area by supporting the delivery of thetreatment device with the medical elongated body.

As an example of the medical elongated body described above,JP-A-2011-135989 discloses a rapid exchange type (monorail type)catheter including a tubular member (i.e., insertion tube) formed with alumen into which a treatment device can be inserted, and a linear body(wire) provided on a proximal side of the tubular member.

The medical elongated body described in JP-A-2011-135989 has a coveringtube overlapping an outer circumferential surface of a proximal portionof the tubular member, and a hook-shaped interlock portion formed bybending a distal portion of the linear body into a U shape. Thehook-shaped interlock portion included in the linear body is connectedto the tubular member via the covering tube in a state where thehook-shaped interlock portion is inserted into the lumen of the tubularmember.

In the rapid exchange type medical elongated body described inJP-A-2011-135989, the lumen is formed only in a tubular body disposed ona distal side, and thus the operator is capable of saving the time andeffort taken to insert the treatment device over the entire length ofthe medical elongated body, and easily inserting the treatment deviceinto the medical elongated body. In addition, the medical elongated bodydescribed in JP-A-2011-135989 has a small area of contact between aguiding catheter which is a parent catheter and the linear body of themedical elongated body. For this reason, the operator is capable ofrather smoothly moving the medical elongated body along a lumen of theguiding catheter.

However, when the rapid exchange type medical elongated body describedin JP-A-2011-135989 is used to support the delivery of the treatmentdevice, problems can occur.

For example, since the tubular member and the linear body are separatemembers, the medical elongated body has a relatively large physicalproperty difference in a connection section between the tubular memberand the linear body. For this reason, when the medical elongated body isdelivered to the vicinity of a lesion area, the medical elongated bodyhas a potential for kinking in the connection section between thetubular member and the linear body.

In addition, in the rapid exchange type medical elongated body, it isnecessary to prevent a proximal opening portion, which is provided onthe proximal side of the tubular member, from moving to a distal side ofthe guiding catheter in the middle of a procedure using the medicalelongated body. For this reason, in the middle of the procedure, it isnecessary for the operator to figure out the position of the proximalside of the tubular member. However, in the medical elongated body, if acontrast marker (contrast ring) typically used in a catheter device isdisposed in the proximal portion of the tubular member, the influence ofthe rigidity of the contrast marker increases a physical propertydifference in the vicinity of a boundary portion between the tubularmember and the linear body. Therefore, the medical elongated body islikely to kink.

Note that in the medical elongated body described in JP-A-2011-135989,as described above, the hook-shaped interlock portion formed in thedistal portion of the linear body overlaps the outer circumferentialsurface of the proximal portion of the tubular member. For this reason,if the linear body and the tubular member are formed of a metallicmaterial, in the medical elongated body, there can be a partialimprovement in the contrast property of the vicinity of the proximalportion of the tubular member. Since the range of a portion of themedical elongated body which has an improved contrast property islimited corresponding to an exterior shape (hook shape) of the linearbody, it can be difficult to improve the contrast property of thevicinity of the proximal portion of the tubular member to a desiredlevel.

In addition, in the medical elongated body, the outer diameter of thedistal portion of the tubular member is preferably set smaller than theouter diameter of the proximal portion of the tubular member. Since themedical elongated body is formed as described above, the distal portionof the tubular member can be delivered relatively smoothly to the lesionarea.

SUMMARY OF DISCLOSURE

A rapid exchange type medical elongated body is disclosed in which anouter diameter of a distal portion of a tubular member is smaller thanan outer diameter of a proximal portion of the tubular member, which canhelp prevent an occurrence of a kink in a physical property changeregion of the medical elongated body which has a relatively large changein physical property, and in which a contrast property of the vicinityof the proximal portion of the tubular member can be improved, and amedical instrument set including the medical elongated body and acatheter.

According to an embodiment of the present disclosure, a medicalelongated body is disclosed, which includes a shaft portion made of alinear body; and a distal member formed on a distal side of the shaftportion and having a lumen, in which the distal member has a firstregion having an inner layer and an outer layer which are made of aresin material, and a second region having the inner layer, the outerlayer, and a tubular member made of a metallic material and disposedbetween the inner layer and the outer layer, in which the tubular memberforming the second region is integrally formed with the shaft portion,in which the distal member has a reinforcement layer containing ametallic material and formed between the inner layer and the outer layerfrom the first region to the second region, in which the reinforcementlayer is disposed inside the tubular member in the second region, and inwhich an outer diameter of the first region is set smaller than an outerdiameter of the second region.

In the medical elongated body with the foregoing configuration, theshaft portion made of a linear body is integrally formed with thetubular member forming the second region of the distal member. For thisreason, in the medical elongated body, a physical property differencecan be kept small at a boundary portion (physical property changeregion) between the shaft portion and the tubular member, and theoccurrence of a kink can be prevented at the boundary portion.

In addition, the medical elongated body with the foregoing configurationis capable of improving the contrast property of the second region byvirtue of the tubular member forming the second region, and thereinforcement layer containing a metallic material and disposed insidethe tubular member in the second region. Therefore, it is not necessaryto separately provide a contrast marker (contrast ring) for indicating aproximal side of the second region, and thus the medical elongated bodyis capable of improving the contrast property of the second region, andpreventing an occurrence of a physical property difference resultingfrom the placement of the contrast marker.

In addition, since the outer diameter of the first region of the distalmember is smaller than the outer diameter of the second region, the easeto insert the medical elongated body with the foregoing configurationinto a body lumen can be improved.

In accordance with another aspect, a medical elongated body is disclosedcomprising: a shaft portion; a distal member formed on a distal side ofthe shaft portion and having a lumen, the distal member having a firstregion, a second region, and a third region, the first region having aninner layer and an outer layer, the second region having the innerlayer, the outer layer, and a tubular member, the tubular member beingdisposed between the inner layer and the outer layer in the secondregion, and an outer diameter of the first region being smaller than anouter diameter of the second region; a reinforcement layer containing ametallic material arranged between the inner layer and the outer layerfrom the first region to the second region of the distal member, thereinforcement layer being disposed inside of the tubular member in thesecond region; and the tubular member having an inclined region inclinedtoward the shaft portion in the third region, the third region includinga proximal opening portion and the third region has an outer diameterincreasing from a distal side toward a proximal side of the inclinedregion.

In accordance with an aspect, a medical instrument set is disclosedcomprising: a medical elongated body which includes a shaft portion madeof a linear body, a distal member formed on a distal side of the shaftportion and having a lumen, the distal member having a first regionhaving an inner layer and an outer layer which are made of a resinmaterial, and a second region having the inner layer, the outer layer,and a tubular member made of a metallic material and disposed betweenthe inner layer and the outer layer in the second region, the tubularmember forming the second region being integrally formed with the shaftportion, a reinforcement layer containing a metallic material arrangedbetween the inner layer and the outer layer from the first region to thesecond region of the distal member, the reinforcement layer beingdisposed inside of the tubular member in the second region, and whereinan outer diameter of the first region is smaller than an outer diameterof the second region; and a catheter having a catheter main body portionwith a lumen into which the medical elongated body is insertable, andwherein a maximum outer diameter of the proximal opening portion of themedical elongated body is equal to or greater than an inner diameter ofthe catheter main body portion

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a simplified view illustrating a medical instrument setaccording to an embodiment of the present disclosure.

FIG. 2 is a perspective view of a medical elongated body according tothe embodiment.

FIG. 3 is an enlarged cross-sectional view of a distal member of themedical elongated body along an axial direction.

FIG. 4 is an enlarged cross-sectional view illustrating a second regionand a third region of the distal member of the medical elongated body.

FIG. 5 is an enlarged view illustrating a portion surrounded by a brokenline 5A of FIG. 3.

FIG. 6 is an enlarged view illustrating a portion surrounded by a brokenline 6A of FIG. 4.

FIG. 7A is an axially orthogonal cross-sectional view of a first regionof the distal member taken along an arrow-head line 7A-7A of FIG. 3.

FIG. 7B is an axially orthogonal cross-sectional view of the secondregion of the distal member taken along an arrow-head line 7B-7B of FIG.3.

FIG. 7C is an axially orthogonal cross-sectional view of the thirdregion of the distal member taken along an arrow-head line 7C-7C of FIG.3.

FIG. 8 is a schematic view illustrating a use example of the medicalinstrument set according to the embodiment.

FIG. 9 is an enlarged cross-sectional view for describing effects of themedical instrument set according to the embodiment.

DESCRIPTION OF EMBODIMENTS

Set forth below with reference to the accompanying drawings is adetailed description of embodiments of a medical elongated body and amedical instrument set representing examples of the inventive medicalelongated body and medical instrument disclosed here. The dimensions orscales on the drawings may be exaggerated or different fromactuality/reality for convenience of description and illustration.

Medical Instrument Set

FIG. 1 illustrates a medical instrument set (catheter set) 10 accordingto the embodiment.

As illustrated in FIG. 1, the medical instrument set 10 has a medicalelongated body 100 and a catheter 200.

In accordance with an exemplary embodiment, the catheter 200 can beconfigured as a so-called guiding catheter that delivers a medicaldevice (for example, a treatment device such as balloon catheter orstent delivery device, or a diagnosis device such as intravascularultrasound diagnosis catheter or intravascular optical diagnosiscatheter) to a lesion area such as stenosed site when a body lumen suchas blood vessel is treated or diagnosed. Generally, the catheter 200 canalso be referred to as a parent catheter.

In accordance with an exemplary embodiment, the medical elongated body100 can be configured as a so-called support catheter that is used for aprocedure such as inserting the medical device, which has been deliveredto the vicinity of the lesion area such as stenosed site by the catheter200, into the lesion area, or such as causing the medical device to passthrough the lesion area. Generally, the medical elongated body 100 isalso referred to as a child catheter.

Catheter

As illustrated in FIG. 1, the catheter 200 has a catheter main bodyportion 210 formed with a lumen 211 into which a guide wire, the medicaldevice, the medical elongated body 100, or the like can be inserted, anda hub 220 disposed in a proximal portion of the catheter main bodyportion 210.

In accordance with an exemplary embodiment, the catheter main bodyportion 210 can be a hollow tubular member having relative flexibility.A distal opening portion 211 a is formed at a distal end of the cathetermain body portion 210, and communicates with the lumen 211 of thecatheter main body portion 210. The catheter main body portion 210 canbe formed of (i.e., made of), for example, a resin material.

In accordance with an exemplary embodiment, the hub 220 of the catheter200 has a Luer tapered connector (Y-connector) 221 that is known in themedical field. The connector 221 has a side branch 223 connected to atubular member through which a contrast agent or a priming liquid canflow; a valve body 224 disposed inside the hub 220; and an opener 225for opening and closing the valve body 224. In addition, a proximal port(not illustrated) configured to receive a shaft portion 110 or a distalmember 120 of the medical elongated body 100 into and out from the hub220 can be provided on a proximal side of the hub 220.

When performing a procedure using the medical elongated body 100, anoperator inserts a distal side (the shaft portion 110 and the distalmember 120) of the medical elongated body 100 into the hub 220 and thecatheter main body portion 210 via the proximal port provided in the hub220 of the catheter 200. If the operator supplies the contrast agentfrom the side branch 223 in a state where the distal side of the medicalelongated body 100 is inserted into the catheter main body portion 210of the catheter 200, the contrast agent can be discharged to a distalside of the catheter main body portion 210. At that time, the operatoris capable of preventing the contrast agent from flowing out from theproximal port of the hub 220 by performing a closing operation of thevalve body 224 of the hub 220.

Medical Elongated Body

As illustrated in FIGS. 1 and 2, the medical elongated body 100 has theshaft portion 110 made of a linear body; the distal member 120 formed ona distal side of the shaft portion 110; and a grip portion 180 which isdisposed on a proximal side of the shaft portion 110 and can be grippedby the fingers of the operator.

As illustrated in FIGS. 1 and 2, the distal member 120 has a firstregion 120A, a second region 120B, and a third region 120C which aredisposed in sequence from a distal side to a proximal side. Note that inFIG. 2, the member number of the main member forming the regions isassigned to each of the regions 120A, 120B, and 120C in order toschematically describe the structure of the distal member 120.

As illustrated in FIGS. 3 and 7A, the first region 120A of the distalmember 120 has an inner layer 130 made of a resin material, and an outerlayer 140 made of a resin material.

Each of the inner layer 130 and the outer layer 140 is formed as ahollow tubular member extending in an axial direction (right and leftdirection in FIG. 3) of the distal member 120.

As illustrated in FIG. 3, the inner layer 130 has a lumen 133 formedinside of the inner layer 130. The lumen 133 of the inner layer 130communicates with a lumen 146 of a proximal portion (a portion of theouter layer 140, which is disposed in the third region 120C) 144 of theouter layer 140. The lumen 133 of the inner layer 130 and the lumen 146of the proximal portion 144 of the outer layer 140 form a lumen 125through which the guide wire, the medical device, or the like isinserted into the distal member 120.

As illustrated in FIG. 3, a distal tip 170 is provided on the distalside of the distal member 120, and helps prevent a distal end of themedical elongated body 100 from causing damages to a body organ when thedistal end comes into contact with a body lumen (intravascular wall orthe like).

The distal tip 170 has a distal opening portion 171 opening at a distalend of the distal tip 170. In addition, the distal tip 170 is fixed (forexample, welded) to the inner layer 130 in a state where the distal tip170 covers a portion of the inner layer 130, which is not covered withthe outer layer 140.

As illustrated in FIG. 5, the outer layer 140 of the distal member 120can have an inclined portion 143 having an outer diameter decreasingfrom a distal end of the second region 120B toward the distal side. Inaccordance with an exemplary embodiment, the inclined portion 143 has across-sectional shape that is curved (i.e., gently curved) from aproximal side to the distal side.

The outer diameter (an outer diameter D1 in the first region 120A) ofthe outer layer 140 in the first region 120A can be, for example, from1.4 mm to 1.8 mm. In addition, the outer diameter (an outer diameter D2in the second region 120B) of the outer layer 140 in the second region120B can be, for example, from 1.7 mm to 2.1 mm.

As illustrated in FIG. 5, in an axially orthogonal cross section of thedistal member 120, a wall thickness t1 of the outer layer 140 in thefirst region 120A closer to the distal side than the inclined portion143 is substantially the same as a wall thickness t2 of the outer layer140 in the second region 120B. Note that the range of substantially thesame dimension contains, for example, a dimensional difference inducedby manufacturing tolerances.

In accordance with an exemplary embodiment, a maximum wall thickness t3of the inclined portion 143 can be greater than the wall thickness t1 inthe first region 120A and the wall thickness t2 in the second region120B. Transition in the wall thickness of the inclined portion 143 ismade such that the wall thickness becomes maximum (i.e., greatest wallthickness) in the vicinity of the distal end of the second region 120Band becomes minimum (i.e., least wall thickness) in the vicinity of aproximal end of the first region 120A.

In accordance with an exemplary embodiment, the outer layer 140 can beformed, for example, by joining together a resin tube (i.e., a tubularmember formed from a resin) forming the first region 120A and a resintube forming the second region 120B. In this case, for example, thetubes (i.e., tubular members) can be welded together by applying heat tothe tubes in a state where the resin tube forming the first region 120Ais covered with the resin tube forming the second region 120B. Inaddition, at that time, the wall thickness of an overlapping portion ofboth tubes (i.e., tubular members) increases by the difference in outerdiameter between both tubular members. In accordance with an exemplaryembodiment, the first region 120A, the inclined portion 143, and thesecond region 120B can be integrally formed, each of which includes apredetermined wall thickness, by adjusting the portion with an increasedwall thickness such that the outer diameter of the portion decreases tothe distal side as illustrated in FIG. 5.

The wall thickness t1 of the first region 120A can be, for example, from0.04 mm to 0.25 mm. In addition, the wall thickness t2 of the secondregion 120B can be, for example, from 0.10 mm to 0.30 mm. In addition,the maximum wall thickness t3 of the inclined portion 143 can be, forexample, from 0.04 mm to 0.40 mm.

As illustrated in FIGS. 3 and 7B, the second region 120B of the distalmember 120 has the inner layer 130; the outer layer 140; and a tubularmember 150 made of a metallic material and disposed between the innerlayer 130 and the outer layer 140.

In accordance with an exemplary embodiment, the tubular member 150forming the second region 120B can be integrally formed with the shaftportion 110 extending to a proximal side of the tubular member 150.

As illustrated in FIGS. 4 and 7B, the tubular member 150 has a hollowtubular structure. In the third region 120C formed closer to theproximal side than the second region 120B, the tubular member 150 has aninclined region 155 inclined toward the shaft portion 110. A proximalopening portion 155 a opening to the proximal side is formed in theinclined region 155.

In accordance with an exemplary embodiment, as illustrated in FIG. 4,the tubular member 150 is connected to and integrated with the shaftportion 110, in a region closer to the proximal side than the inclinedregion 155.

As illustrated in FIGS. 4 and 7C, the distal side of the shaft portion110 is formed into substantially a semicircular arc shape which is theshape of an axially orthogonal cross section. In accordance with anexemplary embodiment, an inner surface 111 of the shaft portion 110 hasa concavely curved cross-sectional shape. Since the shaft portion 110 isformed into substantially a semicircular arc shape as described above,when the shaft portion 110 is inserted into the catheter main bodyportion 210 of the catheter 200, the shaft portion 110 is capable ofreducing a sliding resistance applied between the catheter main bodyportion 210 and the shaft portion 110.

As illustrated in FIG. 2, the shaft portion 110 extends in substantiallya semicircular arc shape to the proximal side on which the grip portion180 is disposed. The grip portion 180 is fixed to the proximal side ofthe shaft portion 110.

As illustrated in FIGS. 3, 7A and 7B, the distal member 120 has areinforcement layer 160 containing a metallic material and formedbetween the inner layer 130 and the outer layer 140 from the firstregion 120A to the second region 120B.

As illustrated in FIG. 7B, the reinforcement layer 160 is disposedinside the tubular member 150 in the second region 120B of the distalmember 120.

As illustrated in FIG. 6, the reinforcement layer 160 has areinforcement member 161 formed of a metallic material, and a gapportion 163 formed in the reinforcement member 161.

In accordance with an exemplary embodiment, the gap portion 163 of thereinforcement member 161 connects together the inner layer 130 and theouter layer 140 in a state where the gap portion 163 is disposed betweenthe inner layer 130 and the outer layer 140. Note that the connectionimplies a state where the inner layer 130 and the outer layer 140 are inphysical contact with each other or a state where the inner layer 130and the outer layer 140 can be, for example, melted and solidifiedtogether.

In accordance with an exemplary embodiment, the reinforcement member 161of the reinforcement layer 160 is formed of a metallic material. Thereinforcement layer 160 has a tubular structure formed by braiding awire rod formed of a metallic material. A braided wire-rod portion formsthe reinforcement members 161, and a mesh portion shaped by thereinforcement members 161 forms the gap portions 163.

The cross-sectional shape of the reinforcement member 161 is notspecifically limited, and can be, for example, a rectangular or circularshape. In addition, for example, a one over and one under pattern inwhich the reinforcement members 161 intersect each other can be adoptedas a braid pattern of the reinforcement member 161.

Note that the reinforcement layer 160 may be formed as, for example, acoil helically shaped along an axial direction.

As illustrated in FIG. 4, the tubular member 150 has a slit portion 153.

As illustrated in FIGS. 4 and 7B, in the second region 120B, the outerlayer 140 can be welded to the inner layer 130 via each gap formed bythe gap portion 163 of the reinforcement layer 160 and the slit portion153 of the tubular member 150.

In order to help enable the inner layer 130 and the outer layer 140 tobe welded together via both of the gap portion 163 and the slit portion153, at least parts of both can be disposed to overlap each other in theaxial direction and a circumferential direction. In accordance with anexemplary embodiment, the foregoing gap is formed in a region where thegap portion 163 and the slit portion 153 overlap each other in the axialdirection and the circumferential direction.

As illustrated in FIG. 4, the slit portion 153 of the tubular member 150is helically formed in the tubular member 150. In addition, a pitch P(axial distance between the slit portions 153 adjacent to each other)between the slit portions 153 can be such that the pitch P decreasesfrom a proximal end toward a distal end of the tubular member 150.

As illustrated in FIG. 6, the tubular member 150 has a plurality ofopening portions 154 in a region closer to a proximal side than a regionwhere the slit portion 153 is formed. Therefore, the outer layer 140 canbe reliably welded to the inner layer 130 via the opening portions 154,in a proximal portion of the tubular member 150 which is likely to comeinto contact with the medical device inserted into the distal member120. Note that each of the slit portion 153 and the opening portion 154is a hole (space) which is actually a non-existing member, but in FIG.6, in order to clearly illustrate a positional relationship betweenboth, the slit portion 153 and the opening portion 154 are illustratedin white.

The opening portion 154 is a hole that passes through the tubular member150 in the wall thickness direction. A specific shape or the number ofthe opening portions 154 is not specifically limited.

Note that if the pitch P of the slit portion 153 of the tubular member150 is such that the pitch P decreases from the proximal end toward thedistal end of the tubular member 150, since the tubular member 150 has asmall number of the slit portions 153 on the proximal side of thetubular member 150, it can be difficult for the gap portion 163 of thereinforcement layer 160 and the slit portion 153 of the tubular member150 to form a gap, and it can be difficult to weld together the innerlayer 130 and the outer layer 140. In this case, since the tubularmember 150 has the opening portion 154 provided closer to the proximalside than the region where the slit portion 153 is formed, the innerlayer 130 and the outer layer 140 can be suitably welded together.

As illustrated in FIG. 5, a distal portion 151 of the tubular member 150can be formed into a tapered shape, the outer diameter of whichdecreases to the proximal side. Note that the shape of an end surface ofthe distal portion 151 of the tubular member 150 is not limited to ashape (rounded shape) which is curved (i.e., gently curved) to thedistal side as illustrated, and for example, a distal surface may have astraight line shape which perpendicularly intersects the axialdirection.

In addition, the tubular member 150 may have a shape in which the innerdiameter and the outer diameter of the tubular member 150 decreases tothe distal side in a stepwise manner or decreases continuously. It ispossible to form the tubular member 150 with the foregoing shape, forexample, the shape is formed by fixing the tubular member 150 to thereinforcement layer 160 with a swage process in a state where thereinforcement layer 160 is covered with the tubular member 150.

As illustrated in FIG. 4, the third region 120C of the distal member 120is formed with a proximal opening portion 145 which is formed of amaterial more flexible than the material of the tubular member 150 andhas an outer diameter increasing from a distal side toward a proximalside of the inclined region 155 of the tubular member 150.

The proximal opening portion 145 formed in the third region 120C isformed on a proximal side of the outer layer 140. In accordance with anexemplary embodiment, the lumen 146 of the proximal portion 144 of theouter layer 140 has a shape which becomes gradually wider (i.e., larger)to the proximal side, and the proximal opening portion 145 is formed ata proximal end of the lumen 146.

As illustrated in FIG. 4, the tubular member 150 has a cylindricaltubular structure in the vicinity of a distal end of the inclined region155 of the tubular member 150. In a cylindrical portion of the tubularmember 150, the tubular member 150 and the reinforcement layer 160disposed inside the tubular member 150 overlap each other in thecircumferential direction. In accordance with an exemplary embodiment,the shape of the tubular member 150 can be gradually transformed fromthe cylindrical shape to the shape (semicircular arc shape) of the shaftportion 110 from the distal side to the proximal side of the inclinedregion 155.

In accordance with an exemplary embodiment, a maximum diameter D3 of theproximal opening portion 145 formed in the third region 120C can be, forexample, substantially equal to or greater than an inner diameter(diameter of the lumen 211) d1 (refer to FIG. 9) of the catheter mainbody portion 210 of the catheter 200. Note that the range ofsubstantially the same dimension, for example, can contain a dimensionaldifference induced by manufacturing tolerances.

In accordance with an exemplary embodiment, if the inner diameter d1 ofthe catheter main body portion 210 of the catheter 200, for example, isfrom 1.4 mm to 2.2 mm, the maximum diameter D3 of the proximal openingportion 145, for example, is preferably from 1.4 mm to 2.2 mm, and morepreferably from 1.7 mm to 1.9 mm.

If it is possible to cause the medical elongated body 100 to protrudefrom the catheter main body portion 210 by a desired length when usingthe medical elongated body 100 along with the catheter 200, the lengthof a portion of the medical elongated body 100 along the axialdirection, which contains the distal member 120 and the shaft portion110, is not specifically limited, and can be, for example, from 800 mmto 1,300 mm. In addition, the length of the distal member 120 along theaxial direction can be, for example, from 100 mm to 300 mm. In addition,the length of the second region 120B of the distal member 120 along theaxial direction can be, for example, from 10 mm to 100 mm. In addition,the length of the third region 120C of the distal member 120 along theaxial direction can be, for example, from 5 mm to 50 mm.

Subsequently, a configuration material of the medical elongated body 100will be described.

In accordance with an exemplary embodiment, the inner layer 130 and theouter layer 140 of the distal member 120 are each preferably made of aresin material more flexible than the material of the tubular member150. The inner layer 130 and the outer layer 140 can be made of, forexample, a polyolefin such as polyethylene, polypropylene, anethylene-propylene copolymer, or an ethylene-vinyl acetate copolymer, athermoplastic resin such as soft polyvinyl chloride, any of variouselastomers such as polyurethane elastomer, polyamide elastomer, orpolyester elastomer, fluorine resin such as polytetrafluoroethylene,polyamide, or a crystalline plastic such as crystalline polyethylene orcrystalline polypropylene.

The distal tip 170 can be made from, for example, a polymer materialsuch as polyolefin (for example, polyethylene, polypropylene,polybutene, ethylene-propylene copolymer, ethylene-vinyl acetatecopolymer, ionomer, or a mixture of two or more of the polymermaterials), polyvinyl chloride, polyamide, polyamide elastomer,polyurethane, polyurethane elastomer, polyimide, or fluorine resin, anymixture of the polymer materials, or a multilayer tubular member made oftwo or more of the polymer materials. Note that the distal tip 170 ispreferably made from a material more flexible than the materials of theinner layer 130 and the outer layer 140.

In accordance with an exemplary embodiment, the shaft portion 110 andthe tubular member 150 can be made from a metallic material, such asstainless steel or super-elastic alloy such as Ni—Ti-based alloy,Ni—Al-based alloy, or Cu—Zn-based alloy.

For example, the reinforcement member 161 of the reinforcement layer 160can be made from the same materials as the exemplary materials of theshaft portion 110 and the tubular member 150.

Subsequently, a use example of the medical instrument set 10 (themedical elongated body 100 and the catheter 200) will be described.

For example, when performing a procedure on a lesion area N such asstenosed site formed in a coronary artery by using a medical device (notillustrated) such as balloon catheter or stent delivery device, anoperator or the like disposes a distal end of the catheter 200 in thevicinity of an entrance of the coronary artery so that the medicaldevice inserted into the catheter 200 can be supported when beingdelivered to the lesion area. However, if the lesion area N such asstenosed site is spaced apart from the vicinity of the entrance of thecoronary artery, even though the distal end of the catheter 200 isdisposed in the vicinity of the entrance of the coronary artery, themedical device may not receive a sufficient support force when beinginserted into the catheter 200. In this case, the operator inserts thecatheter 200 further inside (to the lesion area N) of the coronaryartery, and attempts to deliver the medical device to the lesion area Nin a state where the medical device has received greater support force.

At that time, if the catheter 200 has a relatively large diameter, thecatheter 200 has a potential for causing ischemia or the like. For thisreason, as illustrated in FIG. 8, the operator delivers the medicalelongated body 100, which is thinner, to a distal side of the catheter200 via the catheter 200. Specifically, if the lesion area N such asstenosed site is spaced apart from the vicinity of the entrance of thecoronary artery, before inserting the medical device or after extractingthe medical device from the catheter 200 for the moment, the operatorinserts the medical elongated body 100.

As illustrated in FIG. 9, when delivering the medical device, theoperator delivers the medical elongated body 100 to a desired positionalong a guide wire 300 inserted into the catheter 200. The operator cancause the distal side of the distal member 120 of the medical elongatedbody 100 to protrude from the catheter 200 by a predetermined length,and delivers the medical device via the medical elongated body 100 in astate where the medical device has received a desired support force.

When the medical elongated body 100 is delivered via the catheter 200,as illustrated in FIG. 9, the proximal portion 144 of the outer layer140 is brought into contact with an inner surface of the catheter mainbody portion 210 of the catheter 200. At that time, the proximal portion144 of the outer layer 140 can be flexibly deformed along the innersurface of the catheter main body portion 210, and a clearance betweenthe inner surface of the catheter main body portion 210 and the proximalportion 144 decreases. Therefore, the operator can be capable of rathersmoothly moving the medical elongated body 100 along the catheter 200.In addition, the operator can prevent the medical device, which isinserted into the lumen 125 of the distal member 120 from the proximalopening portion 145 of the outer layer 140, from being caught in theclearance by decreasing the clearance between the proximal portion 144of the outer layer 140 and the inner surface of the catheter main bodyportion 210. Therefore, the operator can rather smoothly insert themedical device into the lumen 125 of the distal member 120.

Furthermore, when supplying the contrast agent from the side branch 223of the catheter 200, the operator can help prevent an occurrence of anevent such as the contrast agent flowing into the clearance between theproximal portion 144 of the outer layer 140 and the inner surface of thecatheter main body portion 210 and being charged in full from the distalopening portion 211 a of the catheter main body portion 210 (refer toFIG. 1). For example, the operator can cause the contrast agent to besent to the distal side of the medical elongated body 100 which hasprotruded to the distal side of the catheter 200, and the contrast agentto be discharged to the lesion area which is a treatment target, and anarea in the periphery of the lesion area. Therefore, the operator canacquire a desired contrast image.

Subsequently, effects of the medical elongated body 100 and the medicalinstrument set 10 according to the embodiment will be described.

The medical elongated body 100 according to the present disclosure hasthe shaft portion 110 made of a linear body, and the distal member 120which is formed on the distal side of the shaft portion 110 and has thelumen 125. The distal member 120 has the first region 120A having theinner layer 130 and the outer layer 140 which are made of a resinmaterial, and the second region 120B having the inner layer 130, theouter layer 140, and the tubular member 150 which is made of a metallicmaterial and is disposed between the inner layer 130 and the outer layer140. The tubular member 150 forming the second region 120B is integrallyformed with the shaft portion 110. The distal member 120 has thereinforcement layer 160 containing a metallic material and formedbetween the inner layer 130 and the outer layer 140 from the firstregion 120A to the second region 120B. Furthermore, the reinforcementlayer 160 is disposed inside the tubular member 150 in the second region120B. The outer diameter of the first region 120A is set smaller thanthe outer diameter of the second region 1206.

In the medical elongated body 100 with the foregoing configuration, theshaft portion 110 made of a linear body can be integrally formed withthe tubular member 150 forming the second region 120B of the distalmember 120. For this reason, in the medical elongated body 100, aphysical property difference in a boundary portion (physical propertychange region) between the shaft portion 110 and the tubular member 150can be kept relatively small, and an occurrence of a kink can beprevented.

In addition, the medical elongated body 100 with the foregoingconfiguration is capable of improving the contrast property of thesecond region 1206 by virtue of the tubular member 150 forming thesecond region 120B, and the reinforcement layer 160 containing ametallic material and disposed inside the tubular member 150 in thesecond region 120B. For this reason, it is not necessary to separatelyprovide a contrast marker (contrast ring) for indicating the vicinity ofa proximal portion of the second region 120B, and thus the medicalelongated body 100 with the configuration as disclosed is capable ofimproving the contrast property of the second region 1208, andpreventing an occurrence of a physical property difference which resultsfrom the placement of the contrast marker.

In addition, since the outer diameter of the first region 120A of thedistal member 120 is smaller than the outer diameter of the secondregion 120B, the ease to insert the medical elongated body 100 with theforegoing configuration into a body lumen can be improved.

In accordance with an exemplary embodiment, the outer layer 140 of thedistal member 120 according to the embodiment has the inclined portion143, the outer diameter of which decreases from the distal end of thesecond region 120B toward the distal side. For this reason, it ispossible to prevent a deterioration in the ease to insert the medicalelongated body 100 which is caused due to the second region 120B beingcaught by the catheter 200, the body lumen, or the like. Therefore, wheninserting the medical elongated body 100 into the body lumen, anoperator can smoothly insert the first region 120A and consecutively thesecond region 120B into the body lumen.

In addition, in the medical elongated body 100 according to theembodiment, in the axially orthogonal cross section of the distal member120, the wall thickness t1 of the outer layer 140 in the first region120A closer to the distal side than the inclined portion 143 issubstantially the same as the wall thickness of the outer layer 140 inthe second region 120B. For this reason, the physical propertydifference in the boundary portion between the first region 120A and thesecond region 120B can be kept relatively small, and an occurrence of akink can be prevented.

In addition, the reinforcement layer 160 according to the embodiment hasthe reinforcement member 161 formed of a metallic material, and the gapportion 163 which is formed in the reinforcement member 161 and connectstogether the inner layer 130 and the outer layer 140. In addition, thetubular member 150 has the slit portion 153. In addition, in the secondregion 120B, the outer layer 140 is welded to the inner layer 130 viaeach gap formed by the gap portion 163 of the reinforcement layer 160and the slit portion 153 of the tubular member 150. For this reason, inthe medical elongated body 100, it is possible to suitably weld togetherthe inner layer 130 and the outer layer 140 which are disposed such thatthe reinforcement member 161 formed of a metallic material and thetubular member 150 formed of a metallic material can be interposed(i.e., placed) between inner layer 130 and the outer layer 140.

In addition, the slit portion 153 of the tubular member 150 according tothe embodiment is helically formed in the tubular member 150. The pitchof the slit portion 153 decreases from the proximal end toward thedistal end of the tubular member 150. For this reason, in the medicalelongated body 100, the flexibility of a distal side (the distal side ofthe tubular member 150) of the second region 120B improves, and thus theease to insert the second region 120B into the body lumen improves.Furthermore, since the tubular member 150 has the plurality of openingportions 154 in the region closer to the proximal side than the regionwhere the slit portion 153 is formed in the tubular member 150, it ispossible to suitably weld together the inner layer 130 and the outerlayer 140 on the proximal side of the tubular member 150 via the openingportions 154.

In addition, the distal member 120 according to the embodiment has thethird region 120C closer to the proximal side than the second region120B. In the third region 120C, the tubular member 150 has the inclinedregion 155 inclined toward the shaft portion 110. The third region 120Cis formed with the proximal opening portion 145 which is formed of amaterial more flexible than the material of the tubular member 150, andthe outer diameter of which increases from the distal side toward theproximal side of the inclined region 155. For this reason, when themedical elongated body 100 is inserted into the catheter main bodyportion 210 of the catheter 200, it is possible to decrease theclearance between the medical elongated body 100 and the catheter mainbody portion 210, and a movement of the medical elongated body 100 withrespect to the catheter 200 becomes relatively smooth. Furthermore, themedical elongated body 100 is capable of improving the ease of insertingthe medical device into the lumen 125 of the medical elongated body 100,and discharging the contrast agent to a proper position inside the bodylumen.

In addition, the medical instrument set 10 according to the embodimentcan include the medical elongated body 100, and the catheter 200 havingthe catheter main body portion 210 formed with the lumen 211 into whichthe medical elongated body 100 can be inserted. In accordance with anexemplary embodiment, the maximum outer diameter of the proximal openingportion 145 of the medical elongated body 100 can be equal to or greaterthan the inner diameter of the catheter main body portion 210. For thisreason, in a procedure using the medical elongated body 100 and thecatheter 200, the medical instrument set 10 can smoothly deliver themedical elongated body 100 and the medical device to a desired positioninside the body lumen, and properly discharging the contrast agent tothe desired position inside the body lumen.

The medical elongated body according to the present disclosure has beendescribed with reference to the embodiment, but the present disclosureis not limited only to the configuration described in the embodiment,and can be appropriately changed based on description of the claims.

For example, the distal member of the medical elongated body may have atleast the first region and the second region, and may not have the thirdregion.

In addition, the cross-sectional shape of the shaft portion of themedical elongated body is not limited to the shape (semicircular arcshape) illustrated, and can be appropriately changed.

In addition, the catheter described in the embodiment is merely anexample, and if the medical elongated body can be inserted into anddelivered by the catheter, the configuration of the catheter is notspecifically limited.

In addition, each configuration part of the medical elongated body canbe replaced with a desired part capable of exhibiting the same function.In addition, a desired component (member) which has not beenspecifically described in the specification may appropriately be addedto the medical elongated body.

The detailed description above describes to a medical elongated body anda medical instrument set. The invention is not limited, however, to theprecise embodiments and variations described. Various changes,modifications and equivalents can be effected by one skilled in the artwithout departing from the spirit and scope of the invention as definedin the accompanying claims. It is expressly intended that all suchchanges, modifications and equivalents which fall within the scope ofthe claims are embraced by the claims.

What is claimed is:
 1. A medical elongated body comprising: a shaftportion made of a linear body; a distal member formed on a distal sideof the shaft portion and having a lumen, the distal member having afirst region having an inner layer and an outer layer which are made ofa resin material, and a second region having the inner layer, the outerlayer, and a tubular member made of a metallic material and disposedbetween the inner layer and the outer layer in the second region, thetubular member forming the second region being integrally formed withthe shaft portion; a reinforcement layer containing a metallic materialarranged between the inner layer and the outer layer from the firstregion to the second region of the distal member, the reinforcementlayer being disposed inside of the tubular member in the second region;and wherein an outer diameter of the first region is smaller than anouter diameter of the second region.
 2. The medical elongated bodyaccording to claim 1, wherein the outer layer of the distal member hasan inclined portion having an outer diameter decreasing from a distalend of the second region toward a distal side of the distal member. 3.The medical elongated body according to claim 2, wherein in an axiallyorthogonal cross section of the distal member, a wall thickness of theouter layer in the first region closer to the distal side than theinclined portion is the same as a wall thickness of the outer layer inthe second region.
 4. The medical elongated body according to claim 1,wherein the reinforcement layer has a reinforcement member formed of ametallic material, and a gap portion formed in the reinforcement memberconnecting the inner layer to the outer layer.
 5. The medical elongatedbody according to claim 4, wherein the tubular member has a slitportion, and wherein in the second region, the outer layer is welded tothe inner layer via a gap formed by the gap portion of the reinforcementlayer and the slit portion of the tubular member.
 6. The medicalelongated body according to claim 5, wherein the slit portion ishelically formed in the tubular member, and a pitch of the slit portiondecreases from a proximal end toward a distal end of the tubular member.7. The medical elongated body according to claim 6, wherein the tubularmember has a plurality of opening portions in a region closer to aproximal side than a region where the slit portion is formed.
 8. Themedical elongated body according to claim 1, wherein the distal memberhas a third region, the third region being closer to a proximal side ofthe distal member than the second region.
 9. The medical elongated bodyaccording to claim 8, wherein the tubular member has an inclined regioninclined toward the shaft portion in the third region, and the thirdregion includes a proximal opening portion and the third region has anouter diameter increasing from a distal side toward a proximal side ofthe inclined region.
 10. The medical elongated body according to claim9, wherein a material of the third region is more flexible than amaterial of the tubular member
 11. A medical instrument set comprising:the medical elongated body according to claim 9; and a catheter having acatheter main body portion with a lumen into which the medical elongatedbody is insertable, and wherein a maximum outer diameter of the proximalopening portion of the medical elongated body is equal to or greaterthan an inner diameter of the catheter main body portion.
 12. Atreatment method for performing a procedure on a lesion inside abiological lumen using the medical elongated body according to claim 1,the method comprising: inserting a guide wire into the biological lumen;inserting a catheter into the biological lumen along the guide wire;delivering the medical elongated body to a position distally of a distalend of the catheter via the catheter and along the guide wire; anddelivering a medical device via the medical elongated body in a statewhere the medical device has received a desired support force.
 13. Amedical elongated body comprising: a shaft portion; a distal memberformed on a distal side of the shaft portion and having a lumen, thedistal member having a first region, a second region, and a thirdregion, the first region having an inner layer and an outer layer, thesecond region having the inner layer, the outer layer, and a tubularmember, the tubular member being disposed between the inner layer andthe outer layer in the second region, and an outer diameter of the firstregion being smaller than an outer diameter of the second region; areinforcement layer containing a metallic material arranged between theinner layer and the outer layer from the first region to the secondregion of the distal member, the reinforcement layer being disposedinside of the tubular member in the second region; and the tubularmember having an inclined region inclined toward the shaft portion inthe third region, the third region including a proximal opening portionand the third region has an outer diameter increasing from a distal sidetoward a proximal side of the inclined region.
 14. The medical elongatedbody according to claim 13, wherein the outer layer of the distal memberhas an inclined portion having an outer diameter decreasing from adistal end of the second region toward a distal side of the distalmember; and wherein in an axially orthogonal cross section of the distalmember, a wall thickness of the outer layer in the first region closerto the distal side than the inclined portion is the same as a wallthickness of the outer layer in the second region.
 15. The medicalelongated body according to claim 13, wherein the reinforcement layerhas a reinforcement member formed of a metallic material, and a gapportion formed in the reinforcement member connecting the inner layer tothe outer layer.
 16. The medical elongated body according to claim 15,wherein the tubular member has a slit portion, and wherein in the secondregion, the outer layer is welded to the inner layer via a gap formed bythe gap portion of the reinforcement layer and the slit portion of thetubular member.
 17. The medical elongated body according to claim 16,wherein the slit portion is helically formed in the tubular member, anda pitch of the slit portion decreases from a proximal end toward adistal end of the tubular member, and wherein the tubular member has aplurality of opening portions in a region closer to a proximal side thana region where the slit portion is formed.
 18. A medical instrument setcomprising: the medical elongated body according to claim 13; and acatheter having a catheter main body portion with a lumen into which themedical elongated body is insertable, and wherein a maximum outerdiameter of the proximal opening portion of the medical elongated bodyis equal to or greater than an inner diameter of the catheter main bodyportion.
 19. A medical instrument set comprising: a medical elongatedbody which includes a shaft portion made of a linear body, a distalmember formed on a distal side of the shaft portion and having a lumen,the distal member having a first region having an inner layer and anouter layer which are made of a resin material, and a second regionhaving the inner layer, the outer layer, and a tubular member made of ametallic material and disposed between the inner layer and the outerlayer in the second region, the tubular member forming the second regionbeing integrally formed with the shaft portion, a reinforcement layercontaining a metallic material arranged between the inner layer and theouter layer from the first region to the second region of the distalmember, the reinforcement layer being disposed inside of the tubularmember in the second region, and wherein an outer diameter of the firstregion is smaller than an outer diameter of the second region; and acatheter having a catheter main body portion with a lumen into which themedical elongated body is insertable, and wherein a maximum outerdiameter of the proximal opening portion of the medical elongated bodyis equal to or greater than an inner diameter of the catheter main bodyportion.
 20. The medical elongated body according to claim 19, whereinthe outer layer of the distal member has an inclined portion having anouter diameter decreasing from a distal end of the second region towarda distal side of the distal member, and wherein in an axially orthogonalcross section of the distal member, a wall thickness of the outer layerin the first region closer to the distal side than the inclined portionis the same as a wall thickness of the outer layer in the second region.